ubuntu - All outgoing mail is marked as spam by gmail

All my emails sent from my SMTP server (created with VespaCP) is being marked as spam by gmail. DNS and DKIM is setup correctly. By using isnotspam.com, I have figured out that the reason is spamassasin giving them a score of 3.7.
Here is the report:

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SpamAssassin check details:
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SpamAssassin 3.4.1 (2015-04-28)


Result: ham (non-spam) (03.7points, 10.0 required)

pts rule name description
---- ---------------------- -------------------------------


* 3.5 BAYES_99 BODY: Bayes spam probability is 99 to 100%
* [score: 1.0000]
* -0.0 SPF_HELO_PASS SPF: HELO matches SPF record
* -0.0 SPF_PASS SPF: sender matches SPF record

* -0.0 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain
* 0.2 BAYES_999 BODY: Bayes spam probability is 99.9 to 100%
* [score: 1.0000]
* 0.1 HTML_MESSAGE BODY: HTML included in message
* -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's
* domain
* 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily
* valid
* -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature
X-Spam-Status: Yes, hits=3.7 required=-20.0 tests=BAYES_99,BAYES_999,

DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HTML_MESSAGE,RP_MATCHES_RCVD,
SPF_HELO_PASS,SPF_PASS autolearn=no autolearn_force=no version=3.4.0
X-Spam-Score: 3.7

I have no clue exactly what is triggering this, I am trying to send verification email with nodejs, but BAYES_99 BODY is triggered regardless of how I send the email or what it contains.